Creating a 3D experience, or the illusion of depth, for a viewer from a two dimensional display panel typically involves displaying a pair of two dimensional images that are slightly offset from each other. The two offset images represent two perspectives of the same scene or object, with deviations that match the perspectives that each eye sees with binocular vision. One of the two images is presented to the viewer's left eye and the other to the viewer's right eye. The viewer's brain then combines these images to perceive depth (known as stereopsis).
There are a variety of different methods for providing the separate images to each eye. In, for example, the time-sequential method using shutter glasses, the display screen alternately displays the left eye and right eye images in a determined time period, such as every other frame. The viewer wears glasses that alternately transmit light to the left eye and the right eye in synchronization with the display screen. The glasses, referred to as shutter glasses or active glasses, block the right eye view when the left eye image is displayed on the display screen, and then block the left eye view when the right eye image is displayed on the display screen. FIG. 1 illustrates a time sequence display of an image using shutter glasses 10 for creating stereopsis. In the first step 11, the left eye image 13 is seen by the left eye through the opening in the shutter glasses 10 and the right eye view 15 is blocked. In the second step 12, the left eye view of the right eye image 16 is blocked while the right eye views the right eye image 16 through the shutter glasses 10. When such a sequence is performed fast enough, typically at a rate of 60 Hz or more, the viewer does not perceive the switching between the two images, but instead the viewer's brain integrates the two offset images into a single, 3D image.
In other methods, referred to as auto-stereoscopic, the viewer is not required to wear glasses. For instance, in the parallax barrier method, as illustrated in FIG. 2, the image for the left eye 21 and the image for the right eye 22 are interleaved for each frame. The display panel includes a parallax barrier 23 having a series of slits 24 positioned so that the right eye image is directed toward and viewed only by the right eye 26, and the left eye image is directed toward and viewed only by the left eye 28. The slits are small enough that they are not perceived by the viewer, and instead, the viewer's brain integrates the images received into the left and right eyes of the viewer into a single, 3D image.